Structural transformations of charged spherical surfactant micelles upon solubilization of water-insoluble polymer chains in salt-free aqueous solutions

2021 ◽  
pp. 118326
Author(s):  
Alexander L. Kwiatkowski ◽  
Vyacheslav S. Molchanov ◽  
Alexander I. Kuklin ◽  
Anton S. Orekhov ◽  
Natalia A. Arkharova ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Structural Transformations ◽  
Polymer Chains ◽  
Surfactant Micelles ◽  
Insoluble Polymer

scholarly journals Effects of the Hydrophilic–Lipophilic Balance of Alternating Peptides on Self-Assembly and Thermo-Responsive Behaviors

2019 ◽  
Vol 20 (18) ◽  
pp. 4604 ◽  
Author(s):  
Ihsan ◽  
Nargis ◽  
Koyama
Keyword(s):  
Aqueous Solutions ◽  
Self Assembly ◽  
Polymer Chains ◽  
Systematic Evaluation ◽  
Solution Temperature ◽  
Critical Solution Temperature ◽  
Hydrophilic Lipophilic Balance ◽  
Upper Critical Solution Temperature ◽  
Cloud Points ◽  
Micellization Behavior

A series of N-substituted poly(Gly–alter–Val) peptides were successfully synthesized for the systematic evaluation of the micellization behavior of alternating peptides. Three-component polymerization employing an aldehyde, a primary ammonium chloride, and potassium isocyanoacetate afforded four alternating peptides in excellent yields. We investigated the dependence of the hydrophilic–lipophilic balance of alternating peptides on the micellization behavior. All the aqueous solutions of alternating peptides exhibited upper critical solution temperature (UCST) behaviors, strongly indicating that the alternating binary pattern would mainly contribute to the UCST behaviors. The cloud points of alternating peptides shifted to higher temperatures as the side chains became more hydrophilic, which is opposite to the trend of typical surfactants. Such unusual micellization behaviors appeared to be dependent on the quasi-stable structure of single polymer chains formed in water.

scholarly journals Miniemulsion copolymerization of (meth)acrylates in the presence of functionalized multiwalled carbon nanotubes for reinforced coating applications

2017 ◽  
Vol 8 ◽  
pp. 1328-1337 ◽  
Author(s):  
Bertha T Pérez-Martínez ◽  
Lorena Farías-Cepeda ◽  
Víctor M Ovando-Medina ◽  
José M Asua ◽  
Lucero Rosales-Marines ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Multiwalled Carbon Nanotubes ◽  
Miniemulsion Polymerization ◽  
Polymer Chains ◽  
Multiwalled Carbon ◽  
Neat Polymer ◽  
In Situ Composites ◽  
3D Network ◽  
Insoluble Polymer

Film forming, stable hybrid latexes made of methyl metacrylate (MMA), butyl acrylate (BA) and 2-hydroxyethyl methacrylate (HEMA) copolymer reinforced with modified multiwalled carbon nanotubes (MWCNTs) were synthesized by in situ miniemulsion polymerization. The MWCNTs were pretreated by an air sonication process and stabilized by polyvinylpyrrolidone. The presence of the MWCNTs had no significant effect on the polymerization kinetics, but strongly affected the polymer characteristics (T g and insoluble polymer fraction). The performance of the in situ composites was compared with that of the neat polymer dispersion as well as with those of the polymer/MWCNT physical blends. The in situ composites showed the presence of an additional phase likely due to the strong interaction between the polymer and MWNCTs (including grafting) that reduced the mobility of the polymer chains. As a result, a substantial increase of both the storage and the loss moduli was achieved. At 60 °C, which is above the main transition region of the polymer, the in situ composites maintained the reinforcement, whereas the blends behaved as a liquid-like material. This suggests the formation of a 3D network, in good agreement with the high content of insoluble polymer in the in situ composites.

Structural transformations in macromolecules of synthetic nonionogenic polymers and DNA in salt-containing aqueous solutions

2007 ◽  
Vol 49 (2) ◽  
pp. 211-216
Author(s):  
E. V. Anufrieva ◽  
M. G. Krakovyak ◽  
T. N. Nekrasova ◽  
R. Yu. Smyslov ◽  
O. V. Nazarova ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Structural Transformations

PHOTOLYSIS OF POLYMETHACRYLIC ACID IN AQUEOUS SOLUTIONS

1964 ◽  
Vol 42 (3) ◽  
pp. 522-531 ◽  
Author(s):  
C. H. Chou ◽  
H. H. G. Jellinek
Keyword(s):  
Aqueous Solutions ◽  
Chain Length ◽  
Polymer Chain ◽  
Irradiation Time ◽  
Polymer Concentration ◽  
Chain Scission ◽  
Polymer Chains ◽  
Polymethacrylic Acid ◽  
Degree Of Ionization ◽  
Ph Values

The photolysis of polymethacrylic acid was studied in aqueous solutions as a function of pH, polymer concentration, polymer chain length, and small additions of electrolytes in the absence of oxygen with light of wavelength 2537 Å. The random chain scission constants decrease with increasing pH values. Small variations in polymer chain length and concentration and electrolyte concentration have no effect on the photolysis. Changes in the ultraviolet spectra with irradiation time are more pronounced at low pH values than higher ones. It is shown that the decrease in susceptibility to photolysis with increasing degree of ionization of the acid is not proportional to the decrease or increase of the number of COOH or COO− groups respectively. It is rather due to the same causes—that is changes in ionic atmosphere— which make the polymer chains uncoil with increasing ionization.

scholarly journals Removal of anthracene from aqueous solutions using modified magnetic Fe3O4 nanoparticles by dendrimer polymer chains and 4-aminophenol Ligandide

2020 ◽  
Keyword(s):  
Aqueous Solutions ◽  
Adsorption Process ◽  
Polymer Chains ◽  
Isotherm Models ◽  
Operational Parameters ◽  
X Ray Diffraction ◽  
Residual Concentration ◽  
Equilibrium Data ◽  
Pseudo Second Order ◽  
The Fourier Transform

Background: Anthracene is an organic compound and environmentally resistant pollutant that causes severe damage to human health due to toxic and carcinogenic properties. The present study aimed to investigate the efficiency of magnetic dendrimer nano-adsorbent for the removal of anthracene from aqueous solutions. Methods: In this study, the synthesized iron oxide nanoparticles were modified by dendrimer polymer chains and 4-aminophenol ligand. The Fourier-transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy were conducted to examine the nano-absorbent properties. Different operational parameters in the adsorption process in batch and laboratory conditions were also studied, and the adsorbent reusability was correspondingly examined in this study. The residual concentration of anthracene in aqueous solution was determined and reported by a spectrophotometer. Findings: Optimization results showed that the maximum adsorbent capacity under optimum conditions (pH=7, 20 mg/L anthracene concentration, 0.5 g/L adsorbent dosage, and 30 min contact time) was equal to 83 mg/g. The experimental data fitted with different isotherm models showed that the equilibrium data were well described by the Langmuir model. In this study, the adsorption process overlapped more with the pseudo-second-order kinetics model. Conclusion: The obtained results indicated that the synthesized nanostructured adsorbent has a high adsorption capacity with high recovery and is efficient enough to remove anthracene from aqueous solutions.

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